Collapsible containers, such as tubes and bottles, made of plastic and metal, are known. When configured as tubes, they are used for accommodating changing positions between objects, such as when a bellows connects two machine parts. When configured as bottles or cans, they are useful for containing beverages and for other purposes to which sealed containers are put.
A typical collapsible container contracts along its axial length. In beverage bottles, this will be either when partially or fully emptied. Thus, such bottles can be sized to the remaining contents, or after use they can be fully collapsed.
Lately, there has been much public attention to the problem of waste disposal, and of recycling of metal and plastic bottles and cans, in particular. Although light in weight, empty containers increase the volume of refuse. Bottles, cans, and other containers which can readily collapse will reduce volume, and thus reduce the cost for collecting and disposing of such things.
Certain patents reflect prior attempts at providing a technically and economically suitable product. U.S. Pat. No. 4,775,564 to Shriver et al. shows a collapsible container having a sidewall with a number of pleats or flutes, like a bellows. U.S. Pat. No. 4,873,100 to Dirksing et al. shows a somewhat similar appearing container, where the successive vertical rings of the container become smaller, thus facilitating the collapse. U.S. Pat. No. 4,865,211 to Hollingsworth describes a collapsible container wherein a smaller diameter base slips inside the larger diameter upper part when axial force is applied. U.S. Pat. No. 5,002,193 to Touzani shows another bellows-like container, where each peak corrugation folds at its outer edge when the collapsing force is applied. U.S. Pat. No. 4,492,313 to Touzani shows another container where each corrugation folds at its outermost peak, and where collapsing is aided by folds in the valley corrugations. U.S. Pat. No. 4,805,788 to Akiho shows a bottle with collapsible sidewall panels. U.S. Pat. No. 4,492,313 to Touzani shows a circular bellows-like sidewall, where the bottom portion of each ring folds under the upper portion when the container is collapsed. U.S. Pat No. 4,790,361 to Jones et al. describes a bottle having corrugations comprised of a multiplicity of polygonal planes.
The prior art indicates that a lot of effort has been applied to making collapsible containers. Still, there is continuing need for improvements in the design and manner of collapse, to provide containers which are dimensionally stable and strong when filled and which are readily collapsible to compact stable shapes.